Q: What are hybrid mana symbols and what do they mean? A: A hybrid mana symbol looks like two different, normal mana symbols squished together into one. For example, this: is a red/white hybrid mana symbol. A hybrid mana symbol can be paid with mana that matches either of its constituent parts.
To give some examples:
A cost of can be paid with either or .
A cost of can be paid with , , or .
A cost of can be paid with , , , or .
A cost of can be paid with one mana of any type, plus either or .
A cost of can be paid with either or two mana of any type.
Q: What color is a hybrid mana symbol? A: A hybrid mana symbol is all of its constituent colors. So a symbol is both blue and red, a symbol is both white and black, and a symbol is green. (It's not colorless, though--colorless is not a color. It's the property of not having any colors.) So something that's looking for, say, the number of green mana symbols on permanents you control will count a hybrid mana symbol that has green as one of its components.
Q: What color is a card with hybrid mana symbols in its mana cost? A: A card is the colors of the mana symbols that appear in its mana cost. This is true no matter what you actually pay when you're casting the spell, and no matter what the card's frame looks like. If a card has a mana cost of , like Slippery Bogle , then it's both green and blue no matter what colors of mana you spend to cast it, because it has both a blue mana symbol and a green mana symbol in its mana cost.
Q: Can I add actual hybrid mana to my mana pool? A: No. There isn't actually any such thing as actual 'hybrid mana'. You have red mana and you have green mana, but no mana that is both red and green at the same time. If something attempts to add an amount of mana to your mana pool that's represented by a hybrid mana symbol, instead, for each of the hybrid symbols, you choose one half of the hybrid symbol, and that's what it adds. So an Elemental Resonance on a Gruul Guildmage , for example, could give you either , , or , but never .
Q: What is the converted mana cost of a card with monocolored hybrid symbols in its cost? (, , etc.) A: When calculating the converted mana cost of a card with monocolored hybrid mana symbols in its cost, each symbol counts as the largest possible number it could be paid with. So a symbol would add 2 to the converted mana cost, because the most it can be paid with is 2 mana. Thus, a card with mana cost (like Flame Javelin ) would always have a converted mana cost of 6, no matter what you spend to cast it.
And so people say to me, "How do I know if a word is real?" You know, anyone who's read a children's book knows that love makes things real. If you love a word, use it! That makes it real. Being in the dictionary is an artificial distinction; it doesn't make the word any more real than any other word. If you love a word, it becomes real. --Erin McKean, Redefining the Dictionary
Q: What "targets"? Does Wrath of God target? What about Giant Growth ? What about Pyroclasm ? A: A spell or ability targets if and only if it uses the word "target", either in the card text itself or in the rules. Giant Growth , for example, targets, because it uses the word "target". Auras, like Holy Strength , also target when you cast them, because the rules say that they do. The Equip ability of Equipment like Leonin Scimitar also targets, because the rules for the Equip keyword say it does. If something doesn't say "target", it doesn't target. Wrath of God and Pyroclasm don't say "target", so they do not target.
Note: The only things that are defined as targeting by the rules (rather than in the actual rules text of the card itself) are Aura spells on the stack and the Provoke, Equip, Modular, Soulshift, Haunt, Fortify, and Reinforce abilities. (Note that enchanting, equipping, and haunting a creature do not target that creature; it's just Auras on the stack and the Equip and Haunt abilities themselves that target.)
Be careful! Some old cards may have confusing, outdated wording that may not properly represent the card's current templating. They may use the word "target" when they don't actually do so. While anything printed after Sixth Edition is generally all right on this score, when dealing with older cards, it's always a good idea to check the Oracle text of the card to see what its current templating is.
Q: What exactly is a legal target for my spell/ability? A: Any targeting requirements for your spells or abilities will be laid out in the "target phrase", which consists of the words directly following the word "target" that describe the nature of the required target. For Aura spells, the target phrase consists of the words directly following the "enchant" keyword.
Balduvian Shaman 's target phrase is "white enchantment you control that doesn't have cumulative upkeep"
Anything that is not part of the target phrase is not part of the targeting requirements, and doesn't matter when it comes time to choose targets. You can target a creature you control with Threaten , for example, because there is no requirement that the target be a creature your opponent controls.
Q: Can I cast/activate a spell or ability without being able to choose all of its targets? A: No. In order to cast/activate a spell or ability, you have to choose legal targets for all of the targets it lays out. If you can't, you can't cast/activate it.
Note that if a spell or ability has multiple possible modes (it says "Choose [some number]--"), then you only have to choose targets for the mode(s) you select. The other modes are treated as though they didn't exist, so you don't have to select targets for them.
Q: What can cause a target to become illegal? A: When a spell or ability tries to resolve, it rechecks its targets. If whatever it was targeting has changed zones since the time the spell or ability's targets were chosen, it is now an illegal target, even if it came back . This is because an object that changes zones "forgets" all about its previous existence and is treated like an entirely new object.
A target can also be illegal if it no longer matches the spell or ability's target phrase (as described above)--if I cast Deathmark on your Kavu Chameleon and you make it blue in response, my Deathmark will be countered, because your Kavu is no longer a "green or white creature" and is thus no longer a legal target for my spell.
Lastly, a target can become illegal if something has come into effect that says the creature can't be targeted--for example, something may have given it Shroud, or you may have somehow gotten a Privileged Position onto the battlefield in response to whatever was targeting it.
Q: What happens if my spell or ability's only target becomes illegal before it resolves? A: When the spell or ability tries to resolve, it is countered by the game rules for having no legal targets. (In player-slang, it "fizzles".) None of its effects occur, even if they didn't have anything to do with the targeted part.
Note: You do not get to change the target of a spell or ability if its original target becomes illegal. You can only change the targets of a spell or ability using a spell or ability that will allow you to do so.
Q: Some spells and abilities have multiple targets. What if some of my spell or ability's targets become illegal, but some remain legal? A: Spells and abilities are only countered on resolution if they no longer have any legal targets. Spells and abilities which have more than one target, but have lost one or more targets still attempt to do as much as they can.
Example: If you cast Pyrotechnics , choosing to do 1 damage to each of 4 creatures but when the spell resolves, only two of those creatures are still on the battlefield, Pyrotechnics still resolves and deals 1 damage to each of the remaining creatures.
Q: I have a spell that lets me change the targets of a spell. Can I use this to cause my opponent's permanent spells to enter the battlefield under my control? A: No, for several reasons. First, permanent spells, with the sole exception of Auras (which target the thing they will enter the battlefield enchanting), have no targets to change; a permanent spell doesn't target the player under whose control it will enter the battlefield. Second, changing a spell's target does not change who controls that spell.
And so people say to me, "How do I know if a word is real?" You know, anyone who's read a children's book knows that love makes things real. If you love a word, use it! That makes it real. Being in the dictionary is an artificial distinction; it doesn't make the word any more real than any other word. If you love a word, it becomes real. --Erin McKean, Redefining the Dictionary
This section has been rewritten and split into two sections, one for the Stack, and one for Priority. See those entries for an explanation of each concept.
And so people say to me, "How do I know if a word is real?" You know, anyone who's read a children's book knows that love makes things real. If you love a word, use it! That makes it real. Being in the dictionary is an artificial distinction; it doesn't make the word any more real than any other word. If you love a word, it becomes real. --Erin McKean, Redefining the Dictionary
Q: What are the different kinds of abilities? A: There are four main categories of abilities: activated abilities, triggered abilities, spell abilities, and static abilities. There is also a special class of abilities called mana abilities, which follow special rules. Activated abilities, triggered abilities, and mana abilities are covered in their own posts below (though there is an explanation of what they are here). If you want to know more about one of those kinds of abilities specifically, see their specific posts. This post covers issues relevant to all kinds of abilities, as well as an explanation of static abilities.
Q: What's an activated ability? A: An activated ability is an ability of a card that reads "{Cost(s)}: {Effect}" (The colon is important--all activated abilities have it.) Some keywords, such as Equip, are also activated abilities. (Check and see if their reminder text has a colon in it.)
See the entry on activated abilities for questions specifically about activated abilities.
Q: What's a triggered ability? A: A triggered ability is an ability of a card that uses the words "When", "Whenever" or "At" to specify a specific event or time and specifies some action that is to occur at that time or when that event occurs. The "At", "When" or "Whenever" usually occurs at the start of the ability, though it may occur someplace else. Triggered abilities may be created for later use by spells or activated abilities.
See the entry on triggered abilities for questions specifically about triggered abilities.
Q: What's a static ability? A: Pretty much everything else--if it's not one of the other kinds of abilities and it's not in italics, it's a static ability. (Anything in italics has no rules relevance, no matter what.)
Static abilities create an effect that is always "on", which we call a continuous effect. They do not use the stack--if the effect changes based on the game state, the effect changes as soon as the state does. For example, if you control a Cranial Plating plus 4 other artifacts, the Plating will give a bonus of +5/+0 to the creature it equips. If you sacrificed one of the artifacts to Krark-Clan Ironworks , the bonus would immediately drop to +4/+0, because you now only control a total of 4 artifacts.
Q: What's a mana ability? A: A mana ability is a special kind of activated or triggered ability. Mana abilities are activated abilities without a target that produce mana and triggered abilities without a target that produce mana and trigger off of a mana ability themselves.
Mana abilities, unlike regular activated or triggered abilities, don't use the stack--they produce their effect immediately. As such, they can't be responded to or countered.
See the entry on mana abilities for questions specifically about mana abilities.
Q: Do abilities "stack" (Are they cumulative)? A: You can always have multiple instances of an ability, but those extra copies may or may not have any added effect. What you really meant is: "Do effects stack"? To get the answer, you need to figure out if multiple instances of the same kind of effect changes anything.
If multiple applications changes anything, they are cumulative; otherwise they aren't. For example, two instances of Flying won't make a creature "fly more", so they don't stack; two instances of Affinity will reduce the cost to cast a spell even more than one, so they do. Having two Leonin Scimitar on a creature will give it +1/+1 and +1/+1, for a total of +2/+2.
An effect that sets a characteristic to a specific value isn't cumulative; it "overwrites" previous values. If two Shifting Sky are out, one set to Green and the other set to Red, they are applied in the order they entered the battlefield. Permanents will be either Green or Red, depending on which one entered the battlefield last.
Q: Do abilities of permanent cards work when the card they're on isn't on the battlefield? A: Not usually. Abilities of permanent cards only work while the card they're on is on the battlefield unless they meet one of three conditions. Either:
The ability specifically states that it works in some other zone. (Carrionette , Genesis )
It's a characteristic-defining ability. (Maro , Mistform Ultimus , Crookshank Kobolds ) Characteristic-defining abilities are abilities of an object that unconditionally define one of that object's characteristic values (color, types, name, mana cost, rules text, power, toughness, expansion symbol, and/or loyalty) as being some specific value.
If the ability does not fall under one of these three categories, it only works while the card it's on is on the battlefield.
For example, the ability "~This~ can't be the target of spells or abilities your opponents control" works only while the card it's on is on the battlefield, because it doesn't state that it works in some other zone and it works perfectly well while on the battlefield. On the other hand, the ability "{Cost}: Return ~this~ from your graveyard to your hand" only works while the card is in the graveyard, because obviously you can't bring the card from your graveyard to your hand if it isn't in your graveyard to begin with.
Q: Will removing the source of an ability stop that ability? (ie, Can I kill something to stop its ability?) A: If you're talking about a static ability, like Blood Moon 's, then yes--removing the permanent it's on turns the ability "off" (because static abilities only work while the card they're on is on the battlefield unless they state or imply otherwise, as explained above). If, however, you're talking about activated or triggered abilities, then no. Once it's on the stack, an activated or triggered ability is completely independent of its source, and won't be affected by anything that happens to that source.
And so people say to me, "How do I know if a word is real?" You know, anyone who's read a children's book knows that love makes things real. If you love a word, use it! That makes it real. Being in the dictionary is an artificial distinction; it doesn't make the word any more real than any other word. If you love a word, it becomes real. --Erin McKean, Redefining the Dictionary
Q: What counts as an activated ability? A: An activated ability is an ability of a card that reads "{Cost(s)}: {Effect}" (The colon is important--all activated abilities have it.) Some keywords, such as Equip, are also activated abilities. (Check and see if their reminder text has a colon in it.) Examples of activated abilities include Anaba Shaman 's damage-dealing ability and Nantuko Husk 's pump ability.
Activated abilities will never do anything on their own--you have to activate the ability in order to produce the effect, and you have to pay the entire cost of the ability in order to do so. After you activate the ability, it goes on the stack like spells do and waits to resolve.
Be careful! Some really old cards (printed before Sixth Edition) have abilities that use colons and are templated like modern-day activated abilities, but that say "Use this ability only when {something happens} and only once per {thing}." See the Fifth Edition version of Crystal Rod for an example. These abilities are not activated abilities; they are triggered abilities.
There also exist even older (Tempest block and earlier) instant and sorcery spells that use a colon; such cards will look (by modern-day standards) like their entire text is one big activated ability. See Fling or AEther Tide for examples. These cards also do not have activated abilities; the colon is used to denote an additional cost of casting the spell, and that cost can only be paid once--that kind of templating isn't used any more.
For these reasons, when dealing with old cards, especially those that were printed before Sixth Edition, it's always a good idea to check the Oracle text of the card to see what its current templating is.
Q: What kinds of activated abilities are mana abilities? A: An activated ability is a mana ability if it doesn't have any targets and can potentially produce mana. It's that simple. Any activated ability that has targets or that can't produce mana isn't a mana ability.
Q: When and how often can I activate an ability? A: Unless the specific ability says otherwise, you may activate any activated ability any time you have priority and as many times as you want, as long as you can pay for it. There are no inherent restrictions on how many times you may use an activated ability.
Of course, some costs might impose inherent limitations on the abilities they pay for--you can't tap a tapped permanent, for example, so any permanent with in its cost can usually only be paid once per round, unless you can find some way to untap it.
Q: I heard there's a limitation on when you can activate abilities of creatures. What's up with that? A: See the entry on Summoning Sickness to learn about this.
Q: Can I pay more for an activated ability in order to "pump it up" and get a bigger effect? A: No. You pay the cost it tells you to pay to get the exact effect it tells you you get; no more, no less. However, you can often activate the same ability several times in a row to get a similar effect.
Q: Will removing or tapping the source of an activated ability stop that ability? A: No. Once an activated ability has been activated, it's completely independent of its source, and nothing that happens to the source will have any effect on the ability itself. (Unless it specifically says so.)
And so people say to me, "How do I know if a word is real?" You know, anyone who's read a children's book knows that love makes things real. If you love a word, use it! That makes it real. Being in the dictionary is an artificial distinction; it doesn't make the word any more real than any other word. If you love a word, it becomes real. --Erin McKean, Redefining the Dictionary
Q: What's a mana ability? A: A mana ability is a special kind of activated or triggered ability, either an activated ability that doesn't have a target and could produce mana, or a triggered ability that doesn't have a target, could produce mana, and triggers off of another mana ability. A mana ability is not "an ability which costs mana to use" (though some mana abilities do cost mana to use).
Mana abilities, unlike regular activated or triggered abilities, don't use the stack--they produce their effect immediately. As such, they cannot be responded to or countered.
Q: When can I activate (activated) mana abilities? A: You can activate activated mana abilities any time you could activate a normal activated ability, and in addition, you may also use such mana abilities any time you are asked to pay mana, even if it's while casting/activating another spell or ability or during the resolution of another spell or ability. Note that you don't activate triggered mana abilities--they just happen on their own when their trigger event (generally you activating some other mana ability) occurs.
Note also that there are some mana abilities that specifically forbid you from activating them at times you couldn't activate a normal activated ability, such as Charmed Pendant 's ability. This is simply to avoid rules complications that arise when weird things happen during the process of casting spells and activating abilities; such abilities are still mana abilities and still cannot be responded to or countered.
Q: I have a spell that produces mana, such as Seething Song . Does it follow the same rules as mana abilities? A: No. Spells that produce mana are the same as any other spell; there are no special rules for such spells, and they can be countered the same way any other spell can be countered.
And so people say to me, "How do I know if a word is real?" You know, anyone who's read a children's book knows that love makes things real. If you love a word, use it! That makes it real. Being in the dictionary is an artificial distinction; it doesn't make the word any more real than any other word. If you love a word, it becomes real. --Erin McKean, Redefining the Dictionary
Q: What's a triggered ability? A: A triggered ability is an ability of a card that reads "[At/When/Whenever] (insert condition or time here), {effect}." Examples of triggered abilities are: Disciple of the Vault 's graveyard trigger, Willbender 's "when I turn face up" ability, and even Decree of Justice 's Soldier-making ability.
When a triggered ability's conditions are met, they trigger and go on the stack. When the trigger resolves, the effect happens.
A special kind, called delayed triggered abilities, can be created by a spell/ability in order to so something later--they'll contain "when", "whenever", or "at" (usually the first or the last) somewhere in the middle. Such delayed triggers will wait around for the appropriate event, trigger, resolve, and then disappear.
There is a special kind of triggered ability that is printed like this: "[Trigger condition], if [additional condition], [effect]." These triggered abilities have what are called 'intervening "if" clauses'; the additional condition is seen as both part of the triggering conditions and part of the effect. The ability will only trigger if the condition is true, and when it resolves the ability will only do something if the condition is still true. If at either time it's not true, the ability won't do anything.
Q: What kind of triggered abilities are mana abilities? A: A triggered ability is a mana ability if it could potentially produce mana, it doesn't have a target, and it triggers off of some other mana ability (usually an activated one).
Q: Will removing the source of a triggered ability stop that ability? A: No. Once it's on the stack, an activated or triggered ability is completely independent of its source, and won't be affected by anything that happens to that source.
Q: Do things "see" other things entering or leaving the battlefield at the same time as themselves? For example, my opponent has a Dingus Staff on the battlefield and casts Obliterate . Would I take damage because my creatures died or not? A: Things always see other things entering or leaving the battlefield at the same time as themselves.
The first step in understanding is the realization that every permanent entering the battlefield and every permanent leaving the battlefield sees itself doing so. (For example, triggered abilities such as Eternal Witness work because the Witness sees itself entering the battlefield. Similarly, Chimney Imp will also trigger when he dies, because he sees himself leaving the battlefield.)
Once this is understood, it logically makes sense that all cards not only see themselves entering or leaving the battlefield, but they also see every other card that does so at the same time they do.
Q: What happens when more than one triggered ability triggers at the same time? A: If more than one triggered ability triggers at the same time, any of those abilities controlled by the active player go onto the stack, then the abilities controlled by each other player go on the stack, in turn order. Each player chooses the order that his or her abilities go on the stack relative to each other. (Remember, Last-In, First-Out. The last ability put onto the stack is the first to resolve.) Then, they all wait to resolve.
Q: If I control something with a triggered ability, can I choose to not have it trigger? A: No, you cannot. If a triggered ability's conditions are met, it will trigger whether you want it to or not. Note: Although you cannot stop them from triggering, some triggered abilities, like Leonin Elder 's, use the word "may" to give you the option on resolution as to whether or not they actually do anything. This is different than the wording of other triggered abilities, like the similar Soul Warden , which do not use the word "may" and must take effect whether you want them to or not.
Q: Can I cast something with an enters-the-battlefield trigger if there are no targets for the ability? A: Yes, you can still cast it. When it enters the battlefield, the ability will trigger, just like normal, but it will be removed from the stack unless there is a legal target. (Note that you must choose a target if it is possible to do so.) Whether there is a target or not, the card with the ability stays on the battlefield.
Q: I have a card with a triggered ability that lets me pay some cost in order to do something. (Such as Circle of Affliction , Mirari , or Frenzied Goblin .) Can I pay the cost multiple times to get the effect multiple times? A: Not unless it specifically says so. The ability says you can pay the cost (once) to get the effect; it does not say you can pay the cost multiple times, and it does not say that you get an increased effect if you pay more. So you can't, and you don't.
If there is more than one trigger, however, you can pay the cost once for each of the triggers. You just can't pay multiple times for the same trigger.
And so people say to me, "How do I know if a word is real?" You know, anyone who's read a children's book knows that love makes things real. If you love a word, use it! That makes it real. Being in the dictionary is an artificial distinction; it doesn't make the word any more real than any other word. If you love a word, it becomes real. --Erin McKean, Redefining the Dictionary
Q: Does dealing damage to a creature reduce its toughness? A: No; that's not how damage works. Damage marked on a creature doesn't reduce toughness; it's simply compared to it. If the amount of damage marked on a creature is equal to or higher than its toughness, it's destroyed. At no time is the creature's toughness reduced. This is important for indestructible creatures, regenerating creatures, and many other effects. And remember, all marked damage is removed from all creatures during the cleanup step of every turn.
Note that the Wither and Infect abilities cause damage to be dealt as -1/-1 counters instead of the normal way; obviously, this changes matters somewhat.
Q: Can a creature be dealt more damage than its toughness? A: Yes; a creature's toughness doesn't limit the amount of damage it can receive. For example, if you block an opponent's Craw Wurm with your Mogg Maniac , the Maniac will take the full 6 damage, (and then deal 6 to your opponent) regardless of the fact that its toughness is only 1.
Q: What counts as "combat damage"? A: Combat damage is damage dealt as part of the process of creatures attacking and blocking during combat. Any other damage is not combat damage, no matter when it is dealt.
Q: When is marked damage removed from a creature? A: All marked damage is removed from each creature during the cleanup step of every turn. (You normally won't be able to do anything after this happens--for more information, see the Turns and the Turn Structure entry of the FAQ.) Marked damage is also removed when a creature regenerates--not when the regeneration spell or ability is cast/activated, but when the regeneration actually takes effect; see the FAQ entry for more information.
Note that since damage from sources with Wither is applied as -1/-1 counters rather than being marked on the creature like normal damage, those counters won't be removed during the cleanup step like normal damage.
Q: I use something to cause damage that would have been dealt to something to be dealt somewhere else instead. Where is this redirected damage coming from? A: Damage that is redirected is still being dealt by the same thing it would have been dealt with without the redirection. If it was combat damage, it is still combat damage.
And so people say to me, "How do I know if a word is real?" You know, anyone who's read a children's book knows that love makes things real. If you love a word, use it! That makes it real. Being in the dictionary is an artificial distinction; it doesn't make the word any more real than any other word. If you love a word, it becomes real. --Erin McKean, Redefining the Dictionary
Q: What does 'summoning sickness' do? A: Creatures with summoning sickness can't attack and can't use abilities with costs that include the or symbols. Creatures have summoning sickness if they have not been under their current controller's control since the beginning of that player's most recent turn.
Q: Can I block with or activate abilities of a sick creature? A: You can block with a creature with summoning sickness, and you can also activate its abilities as long as they don't have or in the cost--summoning sickness only prevents you from attacking and using abilities that include or .
Q: Can I tap/untap a creature with summoning sickness for a cost that doesn't use the or symbols? A: Yes. You're only forbidden from tapping/untapping the creature to pay a or cost. You can still tap/untap the creature to pay for other costs that don't use those symbols.
For example, you can tap a creature with summoning sickness for Convoke; you could also tap three summoning-sick Elves to activate Heritage Druid 's ability, and you can tap Crackleburr and two summoning-sick red creatures to activate Crackleburr 's first ability (The Crackleburr itself can't have summoning sickness, though, because it's paying the cost.)
Q: If a noncreature permanent turns into a creature, does it suffer summoning sickness? (eg, Mutavault ) A: That depends. How long has it been on the battlefield under your control? Summoning sickness only cares about how long that permanent has been on the battlefield under your control; it doesn't care anything about whether or not that permanent was a creature during that time.
So if you play a Mutavault and turn it into a creature that turn, it will suffer from summoning sickness, since you haven't controlled it since the beginning of your most recent turn. But if you turn it into a creature on your next turn, it won't be sick, because you've controlled it since the beginning of your turn. It wasn't a creature at that time, but the game doesn't care about that.
Q: If I take control of my opponent's creature, will it suffer summoning sickness? A: Unless the card that gives you control gives the creature Haste (like on Threaten ), then yes, it will suffer summoning sickness. It doesn't matter how long the creature may have been on the battlefield under your opponent's control; if you haven't controlled it since the beginning of your most recent turn, it will have summoning sickness.
Q: If my creature leaves the battlefield temporarily (Momentary Blink , Astral Slide , etc.), when it comes back, will it have summoning sickness? A: Yes. When the creature comes back onto the battlefield, it is considered a new creature and as such, hasn't been under your control since the beginning of the turn.
And so people say to me, "How do I know if a word is real?" You know, anyone who's read a children's book knows that love makes things real. If you love a word, use it! That makes it real. Being in the dictionary is an artificial distinction; it doesn't make the word any more real than any other word. If you love a word, it becomes real. --Erin McKean, Redefining the Dictionary
Q: How does combat work in Magic? A: During each player's turn, that player has one combat phase. During this combat phase, that player may choose to attack his or her opponent (and/or any planeswalkers that opponent controls) with any number of creatures he or she controls. That opponent (the "defending player") may then choose to use his or her own creatures to block those attacking creatures. Attacking and blocking creatures exchange combat damage, and unblocked creatures deal damage to the player or planeswalker they are attacking.
In order to attack, a creature must be untapped and must not be suffering from "summoning sickness". (Its controller has to have controlled it continuously since the beginning of his or her most recent turn.) The act of attacking causes the creature to become tapped. An attacking creature that's blocked deals combat damage equal to its power divided among the creature(s) blocking it. If it's not blocked, it deals that much damage to the player or planeswalker it's attacking instead. A blocked creature cannot (normally ) deal combat damage to anything other than the creature(s) blocking it.
In order to block, a creature must be untapped. However, blocking doesn't cause a creature to tap and "summoning-sick" creatures can block just fine. Any given creature may (normally ) block only one attacking creature, but any given attacking creature may be blocked by any number of creatures. A blocking creature deals combat damage equal to its power to the creature it's blocking. (If it's somehow blocking more than one creature, the damage is divided among the creatures it's blocking.)
Q: Can I do things during combat... ...before attackers are declared? Q: ...after attackers are declared but before blockers are? Q: ...after blockers are declared but before combat damage is dealt? Q: ...after combat damage is dealt but before combat ends? A: Yes. Combat proceeds through a number of steps, and players have the chance to do things (mainly cast or activate spells and abilities, though there are other possibilities) during each of those steps before the game moves on to the next one.
The first step of combat is called the Beginning of Combat step. Being in the Beginning of Combat step means that the player whose turn it is (the "active player") can no longer cast spells that aren't instants, but no attackers have yet been declared. Players are given a chance to do things during this step, and it's your last chance to do things before attackers are declared. Once everyone's done doing things, the game moves on to the Declare Attackers step.
As the Declare Attackers step begins, the active player chooses his or her attacking creatures and those creatures become tapped and become attacking creatures. (He can choose not to attack if he doesn't want to do so.) This happens first, before players can do anything. After that, players have another chance to do things, and then the game moves on to the next step, Declare Blockers.
As the Declare Blockers step begins, the defending player chooses which creatures (if any) he or she wants to block with and which creature each will block, then those creatures become blocking creatures, and the creatures they're blocking become blocked. (Any attacking creatures which aren't blocked become unblocked creatures.) The active player also decides in which order he or she will assign damage to the creatures blocking his attackers. As in Declare Attackers, this happens before players have the chance to do anything else. Once that's done, players get another chance to do things, and then the game moves on to the Combat Damage step.
As the Combat Damage step begins, each player assigns the damage from his or her creatures. (Assuming there's more than one way it could be done.) Then, that damage is dealt as assigned. After that, players get another chance to do things, and then the game moves on to the End of Combat step.
Nothing much usually happens in End of Combat, but it acts as a "last chance" for players to do things before the game moves back to the active player's second main phase and the active player gets the chance to cast non-instant spells again.
Q: How do I stop an attacking or blocking creature from attacking/blocking? A: If you want to stop a creature from attacking or blocking at all, you need to do something to it before it can be declared as an attacker/blocker that would stop it from doing so, such as tapping it or casting something that says it can't attack or block. However, doing those things after it has already been declared as an attacker/blocker won't somehow make it "un-attack" or "un-block"--it will still be attacking or blocking. The only ways to remove an attacking or blocking creature from combat are to make it leave the battlefield, make it stop being a creature, change its controller, or use something that specifically says it removes it from combat.
Note that removing a blocking creature from combat won't make the creatures it was blocking become unblocked.
Q: My creature is forced (somehow) to attack or block "if able", and there's some additional restriction on how or when it can do so. What happens? (eg, Your opponent provokes your Ember Beast ) A: When the time comes for you to declare attackers/blockers, your creature is forced to do so if it is possible, at that very moment, for you to make it do so somehow. You are required to declare other attackers and so on in order make the attack legal.
However, it's very important to note that while the above is true, nothing is forcing you to take unrelated actions that would then, in turn, make it possible for the requirements to be met so that that creature could attack.
To give an example, imagine your opponent has played Into the Fray on your Ember Beast . When the time comes to declare attackers, if you happen to control at least one other creature that can attack, you are forced to attack with Ember Beast and some other creature. It is possible for you to meet the Beast's requirements, so you must do so. However, now imagine that Ember Beast was your only creature on the battlefield, but you did happen to have a Raging Goblin in your hand and an untapped Mountain with which you could have cast it. Casting the Goblin before combat would later allow your Ember Beast to attack (with the Goblin), but you're not required to do so. Sure, it would allow you to fill the requirement later on, but the game doesn't look that far ahead. It only cares about what you can do right as attackers are being declared, and can only force you to do things right then and there. You aren't required to do anything before that if you don't want to.
And so people say to me, "How do I know if a word is real?" You know, anyone who's read a children's book knows that love makes things real. If you love a word, use it! That makes it real. Being in the dictionary is an artificial distinction; it doesn't make the word any more real than any other word. If you love a word, it becomes real. --Erin McKean, Redefining the Dictionary
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